#define GPBCON  (*(unsigned long*)0x56000010)
#define GPBDAT  (*(unsigned long*)0x56000014)
#define GPBUP   (*(unsigned long*)0x56000018)
#define WTCON   (*(unsigned long*)0x53000000)
int mymain()
{
    WTCON = 0; /* turn off watch dog. */

    unsigned long v = GPBCON;
    v &= 0xFFFc03FF;
    v |= 0x00015400;
    GPBCON = v;

    v = GPBDAT;
    v &= ~0x000001e0;
    GPBDAT = v;    /* turn on all LEDs */

    return 0;
}
